1. Field of the Invention
The present invention relates to use of brazilin in inhibiting the production of cytokines of T helper cell type II (Th2 cell) and/or inhibiting the production of chemokines.
2. Descriptions of the Related Art
Allergic diseases are a kind of common diseases. Mild allergic conditions include those caused by foods or by insect bites, while severe allergic conditions include atopic dermatitis, allergic rhinitis, asthma, and so on. In the last decades, industrialization and development of civilization have caused environmental pollution and changes in people's diet habits. As a consequence, both incidence and severity of allergic diseases are increasing all over the world.
Currently, treatment of allergic diseases still mainly relies on control by medicines. Although anti-allergic medicines, such as corticosteroids, anti-histamines, and anti-leukotrienes, have already been available in the market, there is still around 5% of allergy patients cannot have their conditions got effectively controlled by taking such medicines. Furthermore, each of these medicines has different side effects. For example, the corticosteroids may cause gain of body weight, edema, hypertension, potassium loss, and the like; the anti-histamines may cause lethargy, headache, blurred vision, and the like; and the anti-leukotrienes may cause gastrointestinal discomfort, and so on. Moreover, the greatest problem with these medicines is that, once the patient stops taking the medicines, the allergy symptoms (e.g., inflammatory responses) will relapse within a short time period, so these medicines cannot be used to provide a long-term or long-lasting effect.
On the other hand, allergic diseases may also be treated by taking traditional Chinese medicines. However, traditional Chinese medicines for treating allergic diseases currently available in the market are mostly compound medicines, which still have many problems in terms of medicine preparation and control of dosage and efficacy.
In view of the aforesaid drawbacks of treating allergic diseases with western medicines and traditional Chinese medicines, a need still remains in the art for a substance or pharmaceutical composition that can treat allergic diseases effectively with less side effect and that is easy to prepare.
The present invention is just made to satisfy this need. Through related in vivo and in vitro experiments, the inventors of the present invention confirmed that brazilin can inhibit the production of cytokines of T helper cells type II (Th2 cell) and the production of chemokines, and can deliver a long-term effect of controlling or curing allergic diseases by regulating the fundamental immunologic mechanism.